Menjeda dan Melanjutkan Alur Kerja

Alur kerja akan dijeda dan dilanjutkan sebagai respons terhadap marka buku dan aktivitas pemblokiran seperti Delay, tetapi alur kerja juga dapat secara eksplisit dijeda, dibongkar, dan dilanjutkan dengan menggunakan persistensi.

Menjeda Alur Kerja

Untuk menjeda alur kerja, gunakan Unload. Metode ini meminta agar alur kerja tetap ada dan dibongkar, dan akan menampilkan TimeoutException jika alur kerja tidak dimuat dalam 30 detik.

try  
{  
    // attempt to unload will fail if the workflow is idle within a NoPersistZone  
    application.Unload(TimeSpan.FromSeconds(5));  
}  
catch (TimeoutException e)  
{  
    Console.WriteLine(e.Message);  
}  

Melanjutkan Alur Kerja

Untuk melanjutkan alur kerja yang sebelumnya dijeda dan diturunkan, gunakan Load. Metode ini memuat alur kerja dari penyimpanan persistensi ke dalam memori.

WorkflowApplication application = new WorkflowApplication(activity);  
application.InstanceStore = instanceStore;  
application.Load(id);  

Contoh

Contoh kode berikut menunjukkan cara menjeda dan melanjutkan alur kerja dengan menggunakan persistensi.

static string bkName = "bkName";  
static void Main(string[] args)
{  
    StartAndUnloadInstance();  
}  
  
static void StartAndUnloadInstance()
{  
    AutoResetEvent waitHandler = new AutoResetEvent(false);  
    WorkflowApplication wfApp = new WorkflowApplication(GetDelayedWF());  
    SqlWorkflowInstanceStore instanceStore = SetupSqlpersistenceStore();  
    wfApp.InstanceStore = instanceStore;  
    wfApp.Extensions.Add(SetupMyFileTrackingParticipant);  
    wfApp.PersistableIdle = (e) => {          ///persists application state and remove it from memory
    return PersistableIdleAction.Unload;  
    };  
    wfApp.Unloaded = (e) => {  
        waitHandler.Set();  
    };  
    Guid id = wfApp.Id;  
    wfApp.Run();  
    waitHandler.WaitOne();  
    LoadAndCompleteInstance(id);  
}  
  
static void LoadAndCompleteInstance(Guid id)
{
    Console.WriteLine("Press <enter> to load the persisted workflow");  
    Console.ReadLine();  
    AutoResetEvent waitHandler = new AutoResetEvent(false);  
    WorkflowApplication wfApp = new WorkflowApplication(GetDelayedWF());  
    wfApp.InstanceStore =  
        new SqlWorkflowInstanceStore(ConfigurationManager.AppSettings["SqlWF4PersistenceConnectionString"].ToString());  
    wfApp.Completed = (workflowApplicationCompletedEventArgs) => {  
        Console.WriteLine("\nWorkflowApplication has Completed in the {0} state.",  
            workflowApplicationCompletedEventArgs.CompletionState);  
    };  
    wfApp.Unloaded = (workflowApplicationEventArgs) => {  
        Console.WriteLine("WorkflowApplication has Unloaded\n");  
        waitHandler.Set();  
    };  
    wfApp.Load(id);  
    wfApp.Run();  
    waitHandler.WaitOne();  
}  
  
public static Activity GetDelayedWF()
{  
    return new Sequence {  
        Activities ={  
            new WriteLine{Text="Workflow Started"},  
            new Delay{Duration=TimeSpan.FromSeconds(10)},  
            new WriteLine{Text="Workflow Ended"}  
        }  
    };  
}  
  
private static SqlWorkflowInstanceStore SetupSqlpersistenceStore()
{
     string connectionString = ConfigurationManager.AppSettings["SqlWF4PersistenceConnectionString"].ToString();  
    SqlWorkflowInstanceStore sqlWFInstanceStore = new SqlWorkflowInstanceStore(connectionString);  
    sqlWFInstanceStore.InstanceCompletionAction = InstanceCompletionAction.DeleteAll;  
    InstanceHandle handle = sqlWFInstanceStore.CreateInstanceHandle();  
    InstanceView view = sqlWFInstanceStore.Execute(handle, new CreateWorkflowOwnerCommand(), TimeSpan.FromSeconds(5));  
    handle.Free();  
    sqlWFInstanceStore.DefaultInstanceOwner = view.InstanceOwner;  
    return sqlWFInstanceStore;  
}